Deposition plate to be used as a starter blank or cathode for use in metal refining

ABSTRACT

A deposition plate to be used as a starter blank for producing a starter sheet useful in an electrolytic metal-refining process, the starter blank having a resilient, flexible frame around the peripheral edge thereof. To facilitate the insertion of the starter blank within the frame, as well as the stripping of there starter sheet from the starter blank, a wedge member is associated with the frame, the wedge member being removed from the frame upon insertion of the blank, and being subsequently inserted within the frame so as to lock the frame and blank together. The resilient flexible frame preferably forms a sharp intersection with the starter blank. The plate may likewise be used as a cathode, in which case the resilient, flexible frame does not extend around the entire periphery of the cathode as is the case with the starter blank, but to the contrary, extends only along the longitudinal sides thereof, the bottom portion having been removed. To facilitate stripping of the copper deposits from the cathode plate, the bottom edge of the plate contains an inwardly extending V-shaped groove or notch in lieu of the removed portion of the resilient frame.

March 19, 1974 AKlRA K R ETAL 3,798,151

DEPOSITION PLATE TO BE USED AS A STARTER BLANK OR CATHODE FOR USE IN METAL REFINING 72 Filed Sept. 28, 19 2 Sheets-Sheet 1 YFIG.1 FIG.2

(PRIOR ART) (PRIOR ART) March 19, 1974 AK|RA TAKAMURA EIAL 3,798,151

DEPOSITION PLATE TO BE USED AS A STARTER BLANK OR CATHODE FOR USE IN METAL HEFINING Filed Sept. 28, 1972 I 2 Sheets-Sheet 2 FIG. 3

FIG. 6

\ FIG.7

United States Patent Oflice 3,798,151 Patented Mar. 19, 1974 US. Cl. 204-281 7 Claims ABSTRACT OF THE DISCLOSURE A deposition plate to be used as a starter blank for producing a starter sheet useful in an electrolytic metalrefining process, the starter blank having a resilient, flexible frame around the peripheral edge thereof. To facilitate the insertion of the starter blank within the frame, as well as the stripping of the starter sheet from the starter blank, a wedge member is associated with the frame, the wedge member being removed from the frame upon insertion of the blank, and being subsequently inserted within the frame so as to lock the frame and blank together. The resilient flexible frame preferably forms a sharp intersection with the starter blank.

The plate may likewise be used as a cathode, in which case the resilient, flexible frame does not extend around the entire periphery of the cathode as is the case with the starter blank, but to the contrary, extends only along the longitudinal sides thereof, the bottom portion having been removed. To facilitate stripping of the copper deposits from the cathode plate, the bottom edge of the plate contains an inwardly extending V-shaped groove or notch in lieu of the removed portion of the resilient frame.

BACKGROUND OF THE INVENTION The present invention relates generally to a starter blank, for producing a starter sheet, or cathode, upon which product copper plates may be deposited, for use in an electrolytic metal-refining process and more particularly to an improved starter blank and cathode having an insulating body which provides for improved stripping of the starter sheet or product plates from the starter blank or cathode, and which, is easy to maintain.

As is known in electrolytic refining, such as, for example, in the electrolytic refining of copper, the process for producing a starter sheet or product plates normally includes the steps of depositing upon a starter blank or cathode, respectively, which may be made of various materials, such as, for example, copper or titanium, a copper layer having a thickness of from 0.5 to about 10.0 mm., and subsequently stripping the copper layer i.e., the starter sheet or product plate, from the starter blank or cathode. In connection with such processes, various means have been employed to facilitate the stripping operation as well as obtain a starter sheet or product plate of a given configuration. Such means have included, for example, the use of a vinyl chloride resin frame, having a thickness of from 0.5 to about 2.0 mm., the frame being adhered to the peripheral edges of the starter blank or cathode by the use of an adhesive.

Such means, however suffers from various inherent disadvantages, one major disadvantage being that, in use, the adhesive tends to provide insufficient durability i.e., after a period of several months, part of the resin frames are likely to separate from the blank or cathode. Once this occurs, the copper starter sheet or product plate will tend to deposit upon the separated portion of the resin frame during subsequent electrolysis cycles, thus resulting in further propagated separation due to the subsequent stripping operation of the starter sheet or product plate from the starter blank or cathode. This in turn necessitates the repair of the resin frame itself. In addition, once the resin frame partially separates, the entire resin frame, including the adhesives applied thereon, should be removed from the starter blank or cathode, and a new resin frame, with fresh adhesives, substituted therefor.

Furthermore, where a copper starter blank or cathode is utilized, another difliculty arises from its susceptibility to corrosion and damage due to its softness, such property requiring the utilization of more complex operations as well as the consumption of additional operational time.

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide an improved starter blank or cathode for use in electrolytic metal-refining processes.

Another object of the present invention is to provide an improved starter blank or cathode which has an improved frame mounting to facilitate the stripping operation of the starter sheet or product plate.

Still another object of the present invention is to provide an improved starter blank or cathode of increased durability.

Yet another object of the present invention is to provide an improved starter blank or cathode which will decrease repair and maintenance time.

It is a further object of the present invention to provide an improved starter blank or cathode which simplifies operational procedures and facilitates the reduction of operational time expended.

The foregoing objectives are achieved according to this invention through the provision of a plate, to be used as a starter blank for producing a starter sheet for use in an electrolytic metal-refining process, having a flexible, resilient, U-shaped frame placed upon and around its peripheral edges. To facilitate insertion of the starter blank within the frame member, as well as the stripping of the starter sheet from the starter blank, a wedge is associated with the frame member. To insert the starter blank within frame member, the wedge is removed from the frame member and the notched portions of the frame member which house the Wedge member are squeezed together simulating a lever-and-fulcrum action. Such action consequently spreads the U-shaped portion of the frame member, thereby facilitating easy insertion of the starter blank within the frame. To lock the blank and frame together, the wedges are subsequently inserted within the notched housing portions, thereby simulating a shrink-fitting operation. When the plate is utilized as a cathode, the bottom portion of the frame is removed, and in lieu thereof, the bottom edge portion of the plate is provided with an inwardly extending V-shaped groove or notch, such configuration aiding the stripping process for the cathode similar to that performed by the removed frame portion relative to the starter blank.

BRIEF DESCRIPTION OF THE DRAWINGS Various other objects, features, and attendant advantages of the present invention will be more fully appreciated as the same becomes better understood from the following detailed description when considered in connection with the accompanying drawings, in which like reference characters designate like or corresponding parts throughout the several views, and wherein:

FIG. 1 is a cross-section view of a conventional starter blank showing the starter blank inserted within its insulating frame;

FIG. 2 is an enlarged cross-section view of a starter blank as illustrated in FIG. 1, taken along the line AA of FIG. 1;

bodiment of a starter blank constructed according to this invention;

FIG. 4 is an enlarged cross-section view of another embodiment of a starter blank constructed according to this invention;

FIG. is a cross-section view of a cathode constructed according to the present invention;

FIG. 6 is an enlarged cross-section view of a cathode as illustrated in FIG. 5, taken along line 6--6 of FIG. 5, prior to deposition of the copper product plates; and

FIG. 7 is an enlarged cross-section view of a cathode as illustrated in FIG. 5, taken along line 6-6 of FIG. 5, subsequent to deposition of the copper product plates.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring now to the drawings, and more particularly to FIGS. -1 and 2 thereof, there is shown :a conventional deposition plate 1 for use as a starter blank having a vinyl chloride resin insulating frame 2 fitted upon its peripheral edges, resin frame 2 being substantially U-shaped in cross-section so as to receive within its U-shaped portion, blank 1. As noted heretofore however, the durability of such a vinyl chloride resin frame has proven to be unsatisfactory. In addition, in order to adapt the conventional resin frame for its intended purpose, the body of the frame must of necessity having rather thick walls comprising its U-shape so as to take full advantage of its resilient properties. Such walled configuration however, as disclosed particularly in FIG. 2, causes a deposited copper layer or starter sheet 3 to partially extend over the upper surfaces of resin frame 2 as shown at 4 in such a manner that the deposited copper layer or starter sheet 3 grips the upper portion of frame 2 from above. Hence, when the electrolysis is completed and the starter sheet 3 is subsequently stripped from the starter blank 1 from the upper edge thereof in a direction perpendicular to the starter blank, the deposited copper layer or starter sheet 3 tends to be stuck to frame 2 due to the extended portion 4 of starter sheet 3 covering the upper portion of frame 2 at the lower edge of starter blank 1, in conjunction with the fact that the adhesive, holding frame 2 to blank 1, has already deteriorated, thereby permitting from 2 to separate from blank 1. Consequently, when the starter sheet 3 is stirpped from the starter blank 1, it tends to further separate frame 2 from starter blank 1, thus causing stretching of the frame 2 in addition to such noted separation. This further results in a further loosening of frame 2 relative to blank 1 during subsequent cycles of the electrolysis operation, and such unfavorable conditions may thereby be accelerated by each succeeding stripping operation of starter sheet 3.

Referring now to FIG. 3, one embodiment of the present invention is illustrated, such first embodiment comprising a starter blank 1 having an insulating frame 5 fitted upon its peripheral edges, frame 5 being substantially U-shaped in cross-section so as to receive within its U-shaped portion, blank 1, as at groove 5'.

The material of the starter blank 1, is not necessarily limited to copper. However, in the case of copper electrolysis, the starter blank may be made of copper, titanium or the like and worked or formed according to a cold rolling process.

The frame 5 is made of a resilient material which is not susceptible to any of the electrolytic conditions, such as, for example, any of several rubbers including neoprene rubber, butyl rubber or the like. Frame 5 further includes a triangular notched portion 8 adapted to removably receive a wedge member 6 therein, noted portion 8 being located diametrically opposite the groove portion 5' of frame 5 corresponding to the inserted location of blank 1.

Wedge 6 may have convex or beaded portions 7, 7 on its opposite sides, in which case, the notched portion 8 is the frame 5 would have concave portions 9 and 9' complementary therewith, such interengaging portions serving to prevent the wedge 6 from becoming separated from the frame 5 during the electrolytic operation. The material of the wedge 6 should be one harder than that of frame 5, such as, for example, harder rubber or vinyl chloride. Preferably, such materials should also be heatresistant and acid-resistant.

Still referring to FIG. 3, it is seen that the insulating frame 5 of the present invention provides many advantages over the conventional U-shaped frame, one being for example, that the insulating frame 5 can be easily fitted upon the three peripheral edges of the starter blank 1 Owing to the fact that groove 5' is capable of being spread open by the pressing together of the notched portion 8 when the wedge 6 is not inserted therein, according to a so-called lever and fulcrum principle. In addition, the frame 5 can be firmly fitted or locked upon the peripheral edges of the starter blank 1 by inserting wedge 6 in the notched portion 8, the locking action simulating a shrink-fit.

Furthermore, after the electrolysis, the starter sheet 3 of the present invention may easily be stripped from the starter blank 1 even if the deposited copper layer covers the upper portion of the frame 5 as shown at 4 in FIG. 2, because the insulating frame is firmly fitted or locked with respect to the surfaces of the starter blank 1 because of the groove 5' being pressed together by means of the wedge 6 inserted therein, in the manner heretofore described. This further prevents distortion of or separation of the frame 5 relative to blank 1 when the starter sheet 3 is stripped from the starter blank 1. Accordingly, as there is no possibility of the insulating frame 5 separating from the starter blank 1, stable and sound electrolytic operation is facilitated.

Lastly, extended durability is achieved for the insullating frame 5 because the use of wedge 6 prevents separation of frame 5 from blank 1 and the consequent need for repair or replacement of the frames as is the case with conventional starter blanks. Moreover, ease of the stripping operation of the starter sheet brings about improved productivity of the starter sheets.

Referring now to FIG. 4, a second embodiment of the present invention is disclosed, the rubber frame 5 having lateral surfaces 10, 10 which are tapered toward the starter blank to form a sharp intersection so as to blend into the surfaces of the starter blank 1 in a more streamlined fashion. These tapered or sloped contours in cross section further facilitate the stripping of the starter blank 1 as can readily be appreciated by merely comparing such portions with the corresponding portions of the rubber frames as are shown in FIGS. 2 and 3. Note however, that the degree of taper cannot be too great, for then the locking power of wedge 6 for frame 5 relative to starter blank 1 is diminished. For best results, the included angle from contour to contour should be preferably in the range of from 30-70.

Referring now to FIGS. 5 and 6, there is shown a deposition plate 1, for use as a cathode, of thickness 1, prior to deposition of the copper product plates 3. It is noted that a portion of frame 5 has been removed from the bottom edge portion 11 of cathode plate 1. This is a necessity when utilizing the plate 1 as a cathode, for in such process, the amount of copper deposited upon both surfaces of plate 1 is substantially greater than that deposited when using plate 1 as a starter blank for producing starter sheets. Consequently, if such portion of the frame 5 were not removed, it would be easily damaged by the weight of the copper deposition which tends to accumulate within the bottom area, as may be apparent from reference to FIG. 7.

It is to be remember however, that the frame 5 serves to aid in easily stripping the copper deposits from plate 1 due to the fact that such frame 5 serves as insulation between the two surfaces of copper deposition, i.e., the copper deposits upon both surfaces of plate 1 remain separated. However, due to the fact that a portion of the frame 5 has been necessarily removed along the bottom edge portion 11 of plate 1, the copper deposits are no longer separated, as will be seen from FIG. 7. Consequently, modification of the plate 1 is necessary in order to facilitate easy stripping of the deposits 3 Where frame 5 is absent.

Such modification of plate 1 resides in the provision of a V-shaped groove or notch 12 formed within the bottom edge portion 11 of plate 1. Reference to FIG. 7 will disclose that upon completion of the deposition process, the copper product plates 3 will have adhered to the external surface configuration of plate 1 and consequently will form a division 13, between the two product plates 3, at a point corresponding to the apex 14 of notch 12. As a result of such formation, the two product plates 3 may be divided and split along the division 13, thereby facilitating their easy separation as well as the separation from cathode plate 1.

Obviously, many modifications and variations of the present invention are possible in light of the above teachings. It is to be understood, therefore, that within the scope of the appended claims the present invention may be practiced otherwise than as specifically described herein.

What is claimed as new and desired to be secured by Letters Patent of the United States is:

1. A deposition plate upon which copper deposits may be deposited in an electrolytic metal-refining process, comprising:

an insulator frame member including an elongated flexible element having a groove for receiving an edge portion of said plate therein; and

means diametrically disposed within said frame member relative to said groove for receiving a wedge therein, whereby said frame member is capable of ready insertion along said edge portion of said plate and is capable of being securely fastened there-to by insertion of a wedge within said wedge receiving means.

2. A deposition plate as set forth in claim 1, wherein said plate is made of titanium.

3. A deposition plate as set forth in claim 1, wherein said frame member is made of neoprene rubber.

4. A deposition plate as set forth in claim 1, wherein said frame member has lateral surfaces which are tapered toward said plate so as to blend into the surfaces of said plate in a more streamlined fashion, thereby facilitating the stripping of said copper deposits from said plate. a

5. A deposition plate as set forth in claim 4, wherein the included angle of taper from one lateral surface to the other should be within the range of from 3070.

6. A deposition plate as set forth in claim 1, further comprising a wedge member inserted within said wedge receiving means, said wedge receiving means having complementary convex and concave portions respectively, said portions serving to retain said wedge member within said wedge receiving means during the electrolytic operation.

7. A deposition plate as set forth in claim 1, wherein said plate is provided with a groove disposed Within another edge portion.

References Cited UNITED STATES PATENTS 683,263 9/1901 Elliott et al. 204-281 1,163,337 12/1915 Guggenheim 204281 3,414,502 12/1968 Porrata et al. 204281 3,530,047 9/ 1970 Billett 204-12 FOREIGN PATENTS 145,250 7/1920 Great Britain 204-12 FREDERICK C. EDMUNDSON, Primary Examiner US. Cl. X.R. 204-12 

